IP Telephony & SIP Communication Systems · Guangzhou, China
Scenarios · lifts and vertical transport
An elevator intercom is a life-safety communication chain, and it is judged by one question: if the lift stops between floors, can the person inside speak to someone who can act, and does the equipment still have power when it matters. The design documented here puts the car, the car top, the pit, the machine room and the monitoring desk on one IP and SIP system, over the two or four cores the travelling cable already provides where that is possible. Compliance is the deciding factor in this scenario, not the audio quality, so the page sets out what a compliant design has to answer and which determinations belong to the lift contractor and the local code authority. NEXVIA designs, manufactures, supplies and commissions the system; the terminals and gateways are manufactured by NEXVIA.
Count six positions, not one: the lift car, the car top, the pit, the machine room, the management office and the monitoring centre. That is the six-party arrangement the solution material names for a 2-wire or 4-wire IP elevator intercom gateway (EIM-01), and it is the list to take to a survey: every one of the six is a device, a call route and, where the code requires it, a power arrangement.
The cabling question comes before the equipment question. Where the travelling cable has spare cores, the documented route is the 2-wire or 4-wire technique: the PN1 converter carries network and power over an existing two-core pair and reaches up to 1600 m for the network function without power, supplied at AC 100–240 V, while the PN8 and PN24 switches distribute up to 8 and up to 24 two-wire devices at a maximum connection distance of 300 m for network plus power. Where no spare core exists, the design has to change — not the claim.
The answering side is ordinary telephony, which is what makes the chain testable. A call from the car rings a manned position — an A320i console with 20 SIP lines, up to 116 DSS keys and up to 100 connected devices, or an A330i desk with an RS-485 interface for building signals — and the PBX behind it publishes 24 to 1000 SIP trunks. Prices are not published on this site; the scope is quoted per lift, per position count and per travel-cable condition.
Everything in a lift intercom design runs into the same question: how many spare cores the travelling cable has and what the lift contractor will allow on them. The documented answer for two cores is the 2-wire technique; where no core is available, the design has to change, and that is a conversation with the lift contractor rather than a product selection.
The chain is only as good as its answering position. A manned desk with a console that logs the call, a nominated out-of-hours number and a tested escalation order are what make the system work at 3 a.m.; an unstaffed office with a ringing phone is the failure mode this design has to remove.
The emergency call has to survive the failure that caused the entrapment. The published supply arrangements for the equipment are explicit, but which of them the code requires on a given site is not a product decision — it is agreed with the lift contractor and the code authority, and it is written down.
The pit and car top are where a maintenance technician works alone. The same chain that serves the public in the car serves that technician, and a portable handset such as the W611W keeps the same extension numbers in the technician hand while the fixed positions stay installed.
| Size band | System | Devices | Notes |
|---|---|---|---|
| Single lift in a small building — up to 4 stops | OM20G — 24 SIP trunks; 4 analog ports if an existing lift line is kept | Car station, pit or car-top station, 1 machine-room station, 1 answering phone at the office; 2-wire or 4-wire link per the travelling cable | The OM20G is the only model that can dial out through a 3G/4G USB modem, which matters at a site whose lift line has no wired path. Ring groups hold up to 40 extensions. |
| Two to four lifts in one building | OM50G — 62 SIP trunks; up to 12 analog ports across 3 interface cards | One station per car, per car top, per pit and per machine room, with a shared answering position and a per-lift extension number | Keeping one extension per lift is what lets the person answering know which car is calling without relying on a spoken floor number. Confirm the position list on the quotation. |
| Bank of lifts or a high-rise — 5 lifts and above | OM200G — 496 SIP trunks; up to 96 analog ports on 24-line interface cards | The per-lift position counts repeated, consoles at the monitoring centre, portable handsets for the maintenance team, plant-room extensions | 4 hot-swap card slots, gigabit Ethernet and single or dual AC/DC power; up to 60 extensions in a ring group and group pickup across up to 32 departments. |
| Campus or multi-building estate | OM1000-UC — 1000 SIP trunks, up to 200 concurrent calls per trunk | Per-building lift groups on one dial plan, a central monitoring position with DID numbers per building where required | SIP only, with dual hot standby (3 fixed IP addresses) and multi-site networking using unique or repeatable extension numbering. |
| Retrofit where only spare cores exist | OM50G or OM200G — 62 or 496 SIP trunks | New IP stations at the six positions, with a 2-wire converter on the travelling cable and PN8 or PN24 distribution where several floors are tapped | The published distance figures are the ones to design to: up to 1600 m for the network function without power on PN1, and 300 m for network plus power on PN8 and PN24. Measure the actual cable before committing. |
| Lift with attached building access control | Any model — access control is a separate function on the same system | EC20 IP elevator access controller for floor rights, kept separate from the emergency intercom chain | EC20 drives 64 outputs expandable to 128 over RS485 and Wiegand 26/34 and restricts visitors to designated floors. Keep it a different function from the emergency call: an access controller is not an intercom, and the two should not be conflated in a specification. |
| Position | Device | Published capability | Connection and power |
|---|---|---|---|
| Lift car | Car intercom station on the 2-wire or 4-wire gateway | Two-way voice from the car to the answering position; part of the six-party arrangement the solution material names for the EIM-01 elevator intercom gateway | Carried on the travelling cable via the 2-wire or 4-wire technique; power follows the published converter arrangement and is confirmed on the quotation |
| Car top | Car-top intercom station | Speech from the car top during maintenance or a rescue, through the same gateway | Same travelling-cable route as the car position |
| Car pit | Pit intercom station | Speech from the pit to the answering position; the pit is the position most likely to be occupied by a lone worker | Same travelling-cable route; confirm the mounting and protection with the lift contractor |
| Machine room | A10W panel or an A11-class intercom, or a wall handset (V60G) | A10W: three function keys, a 2W speaker with echo cancellation, one relay and one alarm input for an external emergency button, in a standard 86 box, PoE or 12 V DC at IP54 | One network run or a 12 V DC feed; V60G is wall-mount with dual Gigabit ports |
| Management office | A320i console or an A308i at a smaller desk | A320i: 10.1-inch 1280×800 touchscreen, 20 SIP lines, up to 116 DSS keys, up to 100 connected devices, 92 dB speaker; prioritised calls with colour coding and exportable logs | Dual Gigabit ports with integrated PoE; gooseneck microphone; password-gated emergency calls |
| Monitoring centre | A330i console, with A212 or FH-S01 talkback speakers where the room is also a paging position | A330i: 10.1-inch touchscreen, 116 DSS keys, 92 dB speaker, 8 short-circuit inputs, 1 output and 1 RS-485 interface; A212 publishes talkback and up to 15 W class D | Dual Gigabit with PoE; FH-S01 to IEEE 802.3af; speakers support up to 20 multicast zones with prioritisation |
| Maintenance technician | W611W / W620W portable handset | W611W: IP67, 1900 mAh, up to 9 h talk / 200 h standby, 16 DSS keys and a configurable PTT key. W620W: 3000 mAh, up to 13 h / 240 h, dual microphones, H.264 video preview | Wi-Fi 6 dual-band 2.4G and 5G; IP67 on the W611W suits a wet or dusty plant space |
| Travelling cable and riser | 2-wire or 4-wire technique: EIM-01 gateway, with PN1 converters or PN8 / PN24 switches | Network and power over two cores; PN1 reaches up to 1600 m for the network function without power; PN8 and PN24 carry up to 8 and up to 24 two-wire devices | PN1 external supply AC 100–240 V; PN8 and PN24 built-in supply AC 100–240 V, PN24 in a standard 1U chassis; PN8 and PN24 rated to 300 m for network plus power |
| Building access control (separate function) | EC20 IP elevator access controller | 64 outputs expandable to 128; calls the lift to the first floor ahead of arrival; restricts visitors to designated floors; rights per card or resident | 10/100 Mbps Ethernet; RS485 and Wiegand 26/34; configured over web software |
| Requirement | Conventional dedicated lift telephone | This IP design | What changes operationally |
|---|---|---|---|
| Positions covered | A single car handset wired to a dedicated line | Six positions on one chain — car, car top, pit, machine room, management office and monitoring centre — each an extension or a talkback position | A rescue can be coordinated by voice at both ends of the shaft |
| Answering | A dedicated telephone somewhere in the building, or a line to a call centre | A console with prioritised calls and exportable logs, backed by ring groups and group pickup across up to 32 departments | Who answered and when is in the record |
| Cable route | A dedicated pair, often the only pair available in the travelling cable | The 2-wire or 4-wire technique puts network and power on the existing cores; PN1 reaches up to 1600 m for the network function without power | The retrofit route is a design option rather than a replacement of the travelling cable |
| Testing and records | A functional test at commissioning, then nothing until the next inspection | Call detail records to an external server on port 1809; audio archiving of SIP paging, intercom and calls where the paging tier provides it; call and attendance logs from the console | The chain can be proved after an event, not only before handover |
| Maintenance access | A second handset or an intercom button inside the shaft | W611W or W620W handsets for the technician on the car top or in the pit, on the same extension numbers | Maintenance talk uses the same system, so no separate kit is carried |
| Building integration | None: the lift line is isolated | Machine-room extensions, plant-room phones, paging speakers and access control all sit on the same PBX, with the EC20 handling floor rights | One dial plan, one fault routine and one records feed for the building |
| Area | Device | Note |
|---|---|---|
| Lift car | Car intercom station on the 2-wire / 4-wire elevator gateway | Two-way voice to the answering position, carried on the travelling cable by the 2-wire or 4-wire technique. The solution material names the EIM-01 elevator intercom gateway for this route across the six lift positions; confirm the exact station list and the travelling-cable interface on the quotation. |
| Car top and car pit | Car-top and pit intercom stations on the same gateway | The positions a maintenance technician occupies; the pit is the lone-worker position. Same cable route as the car station, and the same extension numbering so calls can be passed between the car, the pit and the desk. |
| Machine room | A10W panel, or a V60G wall handset | A10W fits a standard 86 box with three function keys, a 2W speaker with echo cancellation, one relay and one alarm input for an external emergency button, on PoE or 12 V DC at IP54. V60G is wall-mount with a 2.4-inch colour screen and dual Gigabit ports. |
| Management office | A320i console (A308i for a smaller desk) | A320i: 10.1-inch 1280×800 touchscreen, 20 SIP lines, up to 116 DSS keys, up to 100 connected devices, 92 dB speaker and an 8 MP camera; prioritised calls with colour coding and exportable call and attendance logs. |
| Monitoring centre | A330i console, with A212 or FH-S01 talkback speakers where the room also pages | A330i: 10.1-inch touchscreen, 116 DSS keys, 92 dB speaker and 8 short-circuit inputs, 1 output and an RS-485 interface for building signals. A212 publishes talkback with up to 15 W class D (PoE 8 W / PoE+ 15 W); FH-S01 reaches up to 20 W on PoE to IEEE 802.3af. |
| Travelling cable, riser and floor distribution | 2-wire converters and switches: PN1, PN8 or PN24 | PN1 carries network and power over an existing two-core pair, up to 1600 m for the network function without power, with an external AC 100–240 V supply. PN8 and PN24 carry up to 8 and up to 24 two-wire devices at a maximum connection distance of 300 m for network plus power; PN24 is a 1U chassis with a built-in supply. |
| Maintenance technicians | W611W / W620W portable handset | W611W: IP67, 1900 mAh, up to 9 h talk / 200 h standby, 16 DSS keys and a configurable PTT key. W620W: 3000 mAh, up to 13 h / 240 h, dual microphones and H.264 video preview; both are Wi-Fi 6 dual-band. |
Six, in the arrangement the solution material names for the elevator intercom gateway: the car, the car top, the car pit, the machine room, the management office and the monitoring centre. Not every position needs a full station — but every position has to be able to reach a person.
That is the design intent of the documented 2-wire and 4-wire technique: network and power travel over two cores. The PN1 converter carries both over an existing two-core pair and reaches up to 1600 m for the network function without power, and the PN8 and PN24 switches distribute up to 8 and up to 24 two-wire devices at a maximum connection distance of 300 m for network plus power.
The published power arrangements are explicit for the parts of the chain this catalogue covers: PN1 and the PN8 and PN24 switches take AC 100–240 V, the A10W accepts PoE or 12 V DC, and the consoles run on PoE. What the chain uses when the building supply fails is a code question, not a product question.
It rings a manned position. The car station places a SIP call to an extension, a ring group or the monitoring console; the console shows the call with priority, and the person who answers has the machine room and the technician on the same system.
Position by position, from the device rather than from a list. Each of the six positions is called in turn, the answering position is confirmed, the reply audio is checked at both ends, and the result is written into the handover document with the date.
Yes, but keep it as a separate function. The EC20 IP elevator access controller drives 64 outputs expandable to 128 over RS485 and Wiegand 26/34, calls the lift to the first floor ahead of arrival and restricts visitors to designated floors.
A portable handset is the practical answer: the W611W is IP67 with a 1900 mAh battery and up to 9 hours of talk time, 16 DSS keys and a configurable push-to-talk key, and the W620W adds a 3000 mAh battery, dual microphones and H.264 video preview.
What the buyer has to confirm, and with whom
| Question | Why it matters | Who confirms it |
|---|---|---|
| What does the applicable lift code require of the alarm device and the two-way voice link? | It sets whether the design can be accepted at all, including the answering location and the indication in the car | The lift contractor and the local code authority |
| Does the travelling cable have spare cores, and may the intercom use them? | It decides between a 2-wire or 4-wire route and a different installation | The lift contractor |
| How is the chain powered, and what happens when the building supply fails? | The emergency call has to remain usable when it is needed; the accepted arrangement is site-specific | The lift contractor and the code authority |
| Who answers, how is it tested, and who keeps the record? | An unanswered call and an untested chain both fail the purpose of the system | The building owner, the monitoring provider and the lift maintenance contractor |
This table is the compliance agenda for the project. Nothing in it is answered by equipment selection, and nothing on this page is a conformity statement.
Lift emergency communication is regulated as part of the lift installation: the national or regional lift code normally states what the alarm device must do, how the two-way voice link to a constantly attended location must behave, what indication the car must give, and how the system is tested and maintained. The published material behind this page cites no lift standard and this page makes no conformity claim — it cannot, because the applicable document is chosen by the country and sometimes by the state or city where the lift is installed. A compliant design is one the lift contractor or the lift owner own code authority has checked against the code that applies on that site, and that check belongs before the equipment is ordered rather than after it is installed.
Two physical questions decide what is possible. The first is the travelling cable: whether it has spare cores, what they are rated for, and whether the lift contractor will allow anything else to be carried on it — a determination that belongs to the lift installation, not to the intercom vendor. Where spare cores exist, the documented route is the 2-wire or 4-wire technique, with PN1 up to 1600 m for the network function without power and PN8 or PN24 up to 300 m for network plus power. The second is the machine room: where the head-end equipment sits, whether it can be reached for maintenance, and whether a network drop and a power outlet can be provided there without interfering with the lift controller. Both answers come from the lift contractor at survey, and both change the equipment list.
The published power arrangements are AC 100–240 V on PN1, PN8 and PN24, PoE or 12 V DC on the A10W panel, and PoE on the consoles and speakers. Whether the emergency communication must continue to work when the building supply fails, for how long, and from what source, is stated by the lift code and is a matter for the lift installation. Confirm with the lift contractor how the intercom chain is fed — from the machine room, from the lift control panel, or from a supply with its own backup — and record the arrangement in the handover document. Do not assume that PoE from a general switch satisfies anything; on most sites it will not be the arrangement the code requires, and the code authority decides what is acceptable.
A lift intercom is not commissioned once and forgotten: the code normally requires the chain to be tested and the test to be recorded, and it can require re-testing after work on the lift. The published tools that support this are call detail records to an external server on port 1809, call and attendance logs exported from the console, and audio archiving of SIP paging, intercom and calls where the paging tier provides it. Write the test procedure — six positions, both audio directions, the answering position and the timestamp — into the handover document, and agree with the lift maintenance contractor who re-tests and who keeps the record. This page describes the technical chain; the testing regime and the retention of its records are local requirements that the lift owner and the code authority confirm.
We have not published a named reference project on this page. The site does not carry customer names or installation records until the client confirms in writing which projects may be made public.
Page author: NEXVIA EngineeringPublished:Last updated:
Covers: elevator intercom · elevator intercom system · lift emergency intercom · elevator intercom requirements · elevator intercom power supply
All IP telephony, intercom and paging equipment in this design is supplied and integrated by NEXVIA.
Running an existing platform
Replacing an older system
Explore Products
Carries network and power over existing two-core cable, for retrofit work.
A wall panel for security calls, intercom and MP3 broadcast.
Android nurse console that answers ward calls and drives the corridor display.
Three interface cards and 62 SIP trunks for offices that keep their analog lines.
Send us the site type, the number of extensions or rooms and the areas to cover — we will come back with a configuration and quotation.
Six facts build a configuration: site type, extensions or rooms, simultaneous calls, areas to cover, existing lines and the documents you already hold. Send as many as you know — nothing has to be final before the first reply.
